THE BIRTH AND LIFE OF THE DEFINITION OF MILITARY OBJECTIVES

Abstract

The forgotten story of the birth and life of the definition of ‘military objectives’ is relevant to the ongoing discussion about the need to adapt the law to asymmetric warfare. This definition, authored by a West German law professor and former member of the Nazi party, was driven by a Western effort to privilege regular armies while curbing the actions of guerrilla fighters and exposing their civilian supporters to harm. The Non-Aligned Movement turned the tide by burdening regular armies while exempting irregular combatants from the consequences of disregarding the law. It was only through judicial intervention—grounded in an imagined history of the linear progress of humanity—that civilians on both sides of asymmetric conflicts would ultimately become entitled to receive adequate protection.

I. INTRODUCTION

The 1960s evoke memories of students vibrantly challenging political and academic authority. Even if these agitations included violent moments, notably in France in May of 1968 and in West Germany in the autumn of that year, they soon morphed into explorations of new ideas about peace and love, as captured by the iconic Woodstock music festival of August 1969. But, for some, Woodstock's message was seen as part of an ominous slippery slope that began with the communists’ manipulation of the young and descended into confrontations and urban guerrillas threatening the political and social order in the West.¹ Among those harbouring such fears was Friedrich August Freiherr (Baron) von der Heydte (hereafter: Heydte), a member of the Institut de Droit International (hereafter: Institut). To him, the transformative events of 1968 signified a new type of war against the West, possibly more perilous than a nuclear one, because ‘[n]uclear wars are avoided, if possible; irregular wars, as a rule, are waged [… and they] give the “have nots” … the possibility of successful resistance also against a “rich” nuclear power’.² In his view, the spread of ‘false ideals’ among the young constituted a crucial first step in irregular warfare.³

While Woodstock's sounds of freedom were still reverberating, Heydte was on his way to Edinburgh, where the 1969 Session of that selective body of international lawyers was about to take place. In that Session, he would oversee the adoption of a Resolution he had authored, which offered a distinction between lawful military objectives and unlawful civilian objectives.⁴ Heydte's text provided a comprehensive response, potentially covering all possible types of military conflicts: symmetric and asymmetric, international and civil, while protecting only the civilians who belonged to nations using regular armies equipped with discerning weapons. Heydte's aim was not only to resolve a century-old effort to protect civilians during hostilities. His primary goal was to develop what he envisioned as a broader legislative response, ‘the international law of tomorrow’, to protect the Western order.⁵ The Resolution's definition of ‘military objectives’ would distinguish between lawful, Western-style attacks and unlawful irregular warfare that thrives on erasing the divide between soldiers and civilians, a war devoid of frontiers, soldiers and military bases.⁶ The Resolution would render such wars prohibited acts, on the basis that they were ‘designed to terrorize the civilian population’.⁷ It would also, by implication, render the irregulars' sympathisers and their dwellings legitimate targets.⁸

The 1969 Resolution was remarkable not only because it achieved a definition of military objectives which had eluded the various actors seeking to modernise the laws of war for years. It was remarkable also because Heydte, the author of the Resolution, was not only a prominent law professor in West Germany, but also had an illustrious career as a daring, high-ranking commander in the army of the Third Reich (the Wehrmacht), who had joined the Nazi party in 1933.⁹

The current scholarly narrative attributes the codification of the laws of war (or IHL, for International Humanitarian Law) to a series of successful campaigns of civil society, led by entrepreneurial Red Cross leaders—from Henry Dunant and Gustave Moynier to Jean Pictet.¹⁰ There are also several realistic explanations emphasising various motivations, from the wish to ensure reciprocity during combat,¹¹ to promoting discipline among the non-professional soldiers in large European armies.¹² More critical voices have proposed that the laws of war reflected the desire of the powerful European nations to privilege military necessity,¹³ enabling armed forces and their political superiors to ‘avoid the hit to [their] reputation that atrocity stories caused’.¹⁴ Those who hold to this interpretation regard the laws of war as deflecting domestic opposition to the use of force, especially during drawn-out ‘forever wars’, and also allowing ‘humanitarian and military professionals’ to avoid exercising ethical and moral judgment.¹⁵

This article describes alternative motives for developing the laws of war: first to protect the political order within Europe by discouraging civilians—at home or in the colonies—from taking up arms,¹⁶ and thereafter, to challenge that order. As this author and Doreen Lustig have shown elsewhere, the codification of IHL to protect the established order was a long-standing motive and the driving force behind the first codification of the laws of war, in 1874.¹⁷ Almost a century later, the Institut's 1969 Resolution can be seen as a similar reaction to what was perceived then as a major, sustained challenge to incumbent regimes. The definition of lawful military objectives was deemed to be necessary to erect an entry barrier for participants in the modern battlefield, privileging those who could employ costlier and more discerning weapons. Irregular combatants whose crude weapons could not properly distinguish among targets would breach international law by using them, and consequentially take away their PoW status and expose them to criminal charges. Branding them as lawbreakers would also undercut the appeal of their fight to easily-swayed youngsters deemed subject to Soviet propaganda.¹⁸ Guerrilla fighters, even the illustrious Che Guevara, would become ‘terrorists’.¹⁹

But the guerrilla fighters would have their own victory in 1977 with the adoption of the two Additional Protocols to the Geneva Convention. Although the first Additional Protocol to the Geneva Convention of 1977 (API)²⁰ adopted Heydte's definition of ‘military objectives’, it effectively retooled the definition to constrain regular armies while relieving irregular combatants of any consequence for ignoring it. This part of the article joins several recent studies of the codification of the laws of war during the 1970s which have focused on the success of the emerging Afro-Asian world in shaping the law to suit its political ends.²¹ While some authors pointed out the victory of the Non-Aligned Movement in expanding the definition of wars to include wars of national liberation, and the definition of prisoners of war (PoW) as encompassing certain irregular combatants,²² this article highlights the Movement's decisive success in shaping the law on the conduct of hostilities.

The proper balance, protecting all civilians equally, would ultimately be achieved through the intervention of judges of international criminal tribunals in the 1990s and 2000s. They would do so by invoking the revered narrative about the linear progression of humanity that is reflected in customary international law. According to this rendition of history, ‘The protection of civilians in time of armed conflict, whether international or internal, is the bedrock of modern humanitarian law.’²³

The forgotten story of the birth and life of the definition of military objectives is relevant to the ongoing discussion about the need to adapt the law to asymmetric warfare. This article shows that the various codification efforts since the 1960s were driven by concerns about asymmetric warfare and reflected a battle between the ‘haves’ and the ‘have nots’. The former used the revered Institut—a West-European body at the time—to pursue their vision of the law applicable in asymmetric warfare, and so did the ‘have nots’ when they could control the agenda of the diplomatic conferences leading up to the 1977 Additional Protocols. Hence, the often-heard argument that the existing law did not intend to restrict action during asymmetric warfare²⁴ is plainly erroneous. Although this type of conflict tests the limits of the law because ‘both sides are convinced that they cannot win the war without violating or at least “reinterpreting” IHL’²⁵ and the observation, invoking the St Petersburg Declaration of 1868,²⁶ that ‘the very philosophy of humanitarian law is challenged by such conflicts’,²⁷ the codification of the principle of distinction was all about asymmetric warfare.

Part II of this article provides some historical background concerning the lacuna at the heart of IHL—the missing definition of lawful ‘military objectives’. Part III uncovers the untold story of the birth of the test for military objectives and of its unsung hero, Professor/Brigadier-General Heydte. Part IV outlines further twists in the winding road toward the inclusive application of Heydte's test. It explains why the Afro-Asian nations that dominated the deliberations over API in the 1970s endorsed this Eurocentric definition of military objectives, and notes the ultimate step—the subsequent judicial extension of the definition also to non-international armed conflicts (NIACs) during the early 2000s. Part V concludes.

II. BACKGROUND: THE QUEST TO CODIFY A DEFINITION OF ‘MILITARY OBJECTIVES’, 1874–1969

The principle of distinction—according to which, during times of war, combatants must direct their attacks only against military objectives while sparing the civilian population—has a long and distinguished pedigree in morality and law. Initially framed in 1762 by Jean-Jacques Rousseau (‘[w]ar … is a relation, not between man and man, but between State and State … and individuals are enemies only accidentally’),²⁸ it developed into the so-called Rousseau–Portalis doctrine, which stipulated that ‘the law of nations does not permit the right of war … to affect peaceful and unarmed citizens’.²⁹ This doctrine was widely recognised throughout the European wars of the early-to-mid-nineteenth century and, as late as 1870, instructed the Prussian Army's invasion of France. As famously articulated by King William of Prussia on 11 August 1870: ‘I conduct war with the French soldiers, not with the French citizens’.

But that doctrine failed to be reflected in the legal code and would soon be abandoned in practice. The rise of nationalism in Europe, the Civil War in the United States and, more generally, the industrialisation of warfare blurred the distinction between military objectives and entirely civilian targets. This retreat from the strict distinction between States and individuals was reflected first in the Lieber Code of 1863, which regarded a ‘citizen or native of a hostile country [as] thus an enemy’.³⁰ The invading Prussian Army soon had to face tenacious civilian resistance, to which it responded harshly. Inspired by the Lieber Code and alarmed at the ugly confrontations with the French francs-tireurs, the German delegates to the 1874 Brussels Conference adamantly opposed the traditional distinction as legally unworkable and unjustified. ‘The goal of any war’, they pronounced, ‘is to crush the enemy, rob him of the means of resistance, and thereby to force his submission. When nations clash and put all their resources in the balance of the battle, it is difficult to determine the limits of warfare.’³¹ Hence, the Rousseau–Portalis formula, which had become one of the prominent principles informing the invitation to the Brussels Conference by Russia (the Chair),³² disappeared from the final text of the Declaration.³³ The sole explicit prohibition in the text of the Declaration relating to civilian targets stipulated that ‘undefended towns’ were immune from attack.³⁴ That was hardly sufficient: it left open the question of what was meant by this term for an army with long-range artillery. It was also unnecessary, as armies of the time would not spend precious ammunition on targets with little military value.

A group of determined international lawyers sought to rectify this lacuna and, more generally, redeem its humanitarian dimension, under the auspices of the Institut, founded, inter alia, to contribute ‘either to the maintenance of peace, or to the observance of the laws of war’.³⁵ Their first major effort in that regard was the so-called Oxford Manual of 1880. But the Institut's subtle innovations failed to make a significant impact on the evolution of the law.³⁶ The Hague Regulations of 1899 (and subsequently, those of 1907) followed the 1874 Brussels text quite closely,³⁷ maintaining the limited protection of civilians only in ‘undefended towns’.³⁸

With the onset of aerial bombardment a few years later, it became clear that the insulation of ‘undefended towns’ was devoid of ‘any practical value’ and civilians were left at the mercy of attacking forces.³⁹ Nevertheless, after the war, no effort was made to address this problem. While aerial bombardments rekindled pity in some quarters toward civilians as their helpless victims,⁴⁰ others saw them as fully responsible for their governments’ choices, and a prevalent proposition suggested that ‘modern warfare … means that every able-bodied civilian plays a definite part in the battle of production’.⁴¹ In the inaugural volume of the British Yearbook of International Law (1920–21), an anonymous article offered a series of arguments against any attempt by the League of Nations to explore this question further.⁴² This view was widespread and was shared by leading scholars such as Lassa Oppenheim and Wolfgang Friedmann.⁴³ Consequently, planners of strategic bombings could claim that every town and village behind enemy lines was ‘defended’ and, as such, a legitimate target.⁴⁴ We now know that, in the view of the Royal Air Force (RAF) since its very inception, harming public morale was regarded as a legitimate and effective military goal. Hence, as Sir Hugh Trenchard, Marshal of the RAF, commented in May 1928, ‘air attacks will be directed against any objective which will contribute effectively towards the destruction of the enemy's means of resistance and the lowering of his determination to fight’.⁴⁵ The German approach was similar.⁴⁶

An effort to have military objectives defined by a commission of jurists comprising delegates from leading countries (the United States, France, Great Britain, Italy, Japan and the Netherlands) failed to gain traction. Instead, they authored the Hague Rules of Air Warfare of 1923,⁴⁷ which contained only an abstract definition⁴⁸ followed by a list of specific examples (military forces, military works, etc). The definition distinguished between the bombardment of towns ‘not situated in the immediate vicinity of the operations of the land forces’⁴⁹ which was forbidden, and civilian areas in the vicinity of the operation of land forces, whose bombardment was legitimate if ‘the military concentration [was] important enough to justify’ it.⁵⁰ These rules were ‘misinterpreted as being too strict’⁵¹ and, at the same time, judged to be impractical.⁵² The convening parties did not pursue the matter further.

After World War II, under the shadow of the atomic bomb, Anglo–American resistance to addressing this question in the drafting of the Geneva Conventions of 1949 led to their limited scope: instead of regulating the conduct of hostilities, the ICRC opted to focus only on the regulation of the hors de combat. Boyd van Dijk shows how the two Western powers (with air-power superiority) successfully blocked communist and ICRC proposals to place limits ‘upon virtually unrestrained air power and Hungerblockade’.⁵³ In the early 1950s, almost simultaneously, the ICRC and the Institut embarked on their respective projects seeking to address the ‘state of chaos’⁵⁴ of the laws on the conduct of hostilities. Although not directly cooperating (or even coordinating their activities), these two bodies were aware of each other's work, and certain individuals served in both. That the road toward codification was fraught with political tensions can be inferred from the fact that the newly-constituted International Law Commission decided not to include the laws of war on its agenda.⁵⁵

The latest initiative of the ICRC was overambitious. Its stated aim was to take ‘all steps to reach an agreement on the prohibition of atomic weapons, and in a general way, of all non-directed missiles’⁵⁶ by making ‘the necessary additions to the [1949] Conventions … to protect civilian populations from the dangers of atomic, chemical and bacteriological warfare’.⁵⁷ Although the ICRC instructed a group of non-government experts to discuss ‘the possibility of giving the civilian population increased protection, by a development of international law, against the dangers of war from the air and the use of blind weapons’,⁵⁸ the threat to nuclear States was significant. The ICRC's Draft Rules were first presented in 1955,⁵⁹ then replaced with a ‘less far-reaching’ draft a year later,⁶⁰ and were ultimately discussed at the ICRC's 1957 conference in Delhi.⁶¹ It was here that the initiative came to a standstill. The aspiration to subject nuclear weapons to ‘the demands of humanity’ and to international law spelled its end.⁶² The ICRC acknowledged that there was minimal governmental support overall, and no support from the governments of the major powers.⁶³ This ICRC project was shelved for the next decade.⁶⁴

Not only was it politically infeasible to arrive at an acceptable definition of military objectives. From a purely technical perspective, the selected group of jurists also found it impossible to articulate a workable formula. Article 7 of the Delhi text offered a question-begging definition, according to which ‘[o]nly objectives belonging to the categories of objective which, in view of their essential characteristics, are generally acknowledged to be of military importance, may be considered as military objectives’.⁶⁵ The definition was complemented by an Annex offering a casuistic list of targets (such as ‘telephone and telegraph exchanges of fundamental military importance’),⁶⁶ and it was suggested that the list ‘be reviewed at intervals of not more than ten years by a group of Experts composed of persons with a sound grasp of military strategy and of others concerned with the protection of the civilian population’.⁶⁷ The task of capturing the essential elements of military objectives was left to the lawyers at the Institut.

III. THE EDINBURGH RESOLUTION OF 1969: A CONSERVATIVE LEGAL BREAKTHROUGH

That crucial, comprehensive and effective definition of a military objective would ultimately be fleshed out by the Institut at its 1969 meeting in Edinburgh.⁶⁸ This Part tells the story of the meandering path taken by the Institut toward that momentous Resolution. Here, the article dwells on the persona of the author of the Resolution because his identity and ideology offer a key to understanding the motivation for its adoption.

Heydte does not conform to the archetype of the humanistic visionary associated with the development of the laws of war and the founding of the Red Cross and the Institut. Combining two illustrious careers—as a prominent law professor and conservative public intellectual, and as a paratrooper who had fought the most daring battles of World War II as a commander in an elite unit of the Wehrmacht and later joined the Bundeswehr as a Brigadier-General—Heydte devoted his post-war life to fending off what he saw as a communist onslaught on the fabric of Christian Europe. This Resolution would be yet another chapter in his lifelong mission. For Heydte, ‘preparing for battle’ was in his blood. A proud descendant of (French and German) families who had fought for or against European monarchs for generations, he remained committed to protecting the Vaterland against all evil. Tellingly, his autobiography ends with his family's timeworn poem which begins with ‘I must strive, I want to die, to die for my Fatherland’.⁶⁹

By the late 1960s, the Institut was the last international-law bastion of the West. By 1969, this august, self-selecting body had elected only six members from Asian and African nations⁷⁰ to its 81-strong group of experts. In contrast, the Red Cross movement had been transformed during those years from an almost exclusively West-European impulse that consulted predominantly Western ‘highly qualified experts’ in the laws of war in 1954,⁷¹ to a much more inclusive body. The 1969 Istanbul Conference of the International Committee of the Red Cross (ICRC) saw delegates representing 77 countries and 83 National Committees participating in its effort to develop the laws of war.⁷² During that period, the United Nations’ International Law Commission had also begun to reflect the emerging new world, with more than a third of its membership coming from Asian and African nations.⁷³ The Institut, then, still unaffected by decolonisation, provided the optimal venue for Heydte's mission.

Recently initiated to the Institut as an Associate Member, he took up the task of codifying the principle of distinction in international and internal armed conflicts to tackle what he saw as a menacing challenge for the West. His intellectual brilliance and his deep understanding of the battlefield enabled him to conceptualise what had eluded his predecessors and express it in brief, elegant prose. Within weeks, Heydte's test would be embraced by the ICRC at its Istanbul Conference later that month, and would become a crucial pillar of API.

A. Initial Steps, 1952–59

The Institut's initiative to study the laws surrounding the conduct of hostilities commenced in 1952, with a study led by Frederic Coudert, Jean Pierre Adrien François and Hersch Lauterpacht.⁷⁴ They trod cautiously. Lauterpacht had expressed doubts earlier concerning the creation of new law that was ‘not necessarily related to any existing generally recognized legal principles’.⁷⁵ In his view, at that time, the Rousseau–Portalis doctrine had become a ‘hollow phrase’ and a ‘relic of the past’, due to the increased reliance on civilians engaged in work of direct military importance, the growth of the destructive power of aircraft, and the growing role of the economic weapon, ‘which render[ed] practically impossible, in this respect, a differentiation between civilians and combatants’.⁷⁶ The 1954 report by Coudert, François and Lauterpacht⁷⁷ stated that the laws of war were outdated and not reflective of contemporary means of warfare.⁷⁸ The authors highlighted the difficulty of limiting the rights of belligerents out of humanitarian concerns but nevertheless suggested that a commission be formed to examine certain principles that, if necessary, could serve as a starting point for the codification of the laws of war.

The report convinced the Institut to form the twenty-fifth Commission on the ‘Reconsideration of the Principles of the Law of War’,⁷⁹ whose interim report was presented at the Institut's 1957 session.⁸⁰ Reflecting the members’ acute sense of the politically feasible, the 1954 report sought to evade the challenge of directly regulating nuclear weapons. Whereas ‘[a]n agreement on the limitation or prohibition of these weapons [was] necessary’, for the time being, it would be feasible to emphasise that ‘the use of these weapons should be limited to military objectives’.⁸¹ Hence the report proposed a strengthening of the distinction between military and non-military objectives by revising the definition adopted in the Hague Rules of 1923.⁸²

But even that was a difficult mission. In the Commission's plenary discussions of 1959,⁸³ François and others sensed that the situation was not yet ripe for attempting to draft a resolution. More time and effort were needed. The Institut therefore resolved to form three new commissions to further study certain aspects: one dealing with the equal application of the rules of the law of war to aggressor and victim alike, one addressing the problems posed by the existence of weapons of mass destruction, and one (the Fifth Commission) devoted to the distinction between military and non-military objectives.⁸⁴ With the first two being subsequently discontinued, the Fifth Commission was the only one to produce a resolution.

B. The Appointment of Heydte as Rapporteur, 1959

The Institut elected Heydte as the Rapporteur of the Fifth Commission.⁸⁵ In many respects, he was particularly apt for this task, his rich legal background being matched by his military expertise. At the time, he was the Head of the Institute for Military Law at the University of Würzburg, as well as an active member of the Bundeswehr. In 1955, at the behest of the West German Government, Heydte helped build Egypt's paratrooper and airborne forces,⁸⁶ and in 1962 he was promoted to the highest rank of Brigadier General in the Reserves. A descendant of a family of warriors, a conservative for whom democracy was ‘Christian in its essence’ and entailed a ‘[d]emocratic responsibility [that can] only [be] fulfilled in the community’,⁸⁷ Heydte regarded his by-and-large lone effort to develop the neglected field of the laws of war⁸⁸ as a calling that combined his two disciplines.

Heydte's academic trajectory could have been different. When the Nazis came to power, he was about to study for a habilitation (a second doctorate) with Hans Kelsen.⁸⁹ But Kelsen was dismissed, and his successor, Carl Schmitt, did not trust Heydte.⁹⁰ Even Heydte's joining the Nazi Party (NSDAP) the day after Kelsen's removal⁹¹ did not change Schmitt's view, perhaps because Heydte campaigned publicly for his teacher.⁹² Heydte went on to study with Alfred Verdross in Vienna, but an altercation with some Nazi Party members forced him to flee and join the Wehrmacht. He would become one of the most committed, daring and accomplished commanders of the Wehrmacht throughout the war. Despite his disillusionment with the Nazi regime, ‘The Rosary Paratrooper’, as Hermann Göring would cynically dub him, was assigned to lead the most ambitious last-ditch attack in the Ardennes.⁹³ He is said to have abided by the laws of war and even acted chivalrously, at one point returning captured American paramedics to enable them to resume their duties among wounded US troops, and hoping this gesture would be returned if the need arose.⁹⁴ But he was well aware of prevalent violations. In the late 1990s, it came to light that, during the war, Heydte had known about the systematic gassing of Jews⁹⁵ and about atrocities committed against Polish Jews⁹⁶ and Russian villagers.⁹⁷

Just before his election to the Institut on 11 April 1956,⁹⁸ Heydte was embroiled in a highly-publicised parliamentary crisis that saw him resign from the chairmanship of the Abendländische Akademie (Occidental Academy),⁹⁹ an institution regarded by many in West Germany as anti-constitutional as it sought to transform West Germany ‘into a clerical, authoritarian and monarchist corporate state’.¹⁰⁰ That Academy perceived communism as a threat to Europe's survival; and, to counter it, it promoted a conservative vision of ‘democracy’—one that sought to emulate Franco's Spain and Salazar's Portugal. And, indeed, during a speaking tour across Spain, Heydte called for a collective Christian effort against liberal values.¹⁰¹ In 1956, Heydte was also busy leading a constitutional challenge against the dismantling of the denominational-schools system in Lower Saxony, seeking to preserve exclusionary religious schools in Germany.¹⁰² As a public intellectual, Heydte rejected the liberal–individual vision of democracy and criticised the Basic Law's rejection of federalism as a palliative against the ‘instinctuality of the masses’, preferring respect for ‘divine moral law’ and individual freedom as necessarily defined by Christian community.¹⁰³

Throughout his association with the Institut, Heydte remained a controversial figure in the German-speaking community. In 1961, his formal offer to succeed Verdross in Vienna was intercepted by the Socialist Party of Austria (SPÖ).¹⁰⁴ In 1962, he triggered the infamous ‘Der Spiegel affair’ (when he accused news magazine Der Spiegel of high treason following its publication of sensitive military information), which developed into a major political scandal and a serious legal crisis.¹⁰⁵ He was also a target of students’ ire—for example, in a protest in the Freie Universität Berlin against inviting this ‘clerical-fascist-thinking’ professor to give a public lecture.¹⁰⁶

Heydte was preoccupied with the threat posed by irregular warfare to Western civilization. In his view, the Christian West was fighting for survival against the USSR's turn to irregular means of warfare, which included implanting ‘false ideals’ in young European minds. He regarded the 1968 students’ revolution as nothing but a consequence of the successful irregular warfare fought by the Soviets against Europe.¹⁰⁷ Heydte saw his fight as part of his life's mission to save European civilisation from communism, which, he believed, was relentlessly seeking to destroy it through irregular warfare.¹⁰⁸

In 1961, he wrote about atomic and guerrilla warfare as the two primary challenges to the international law of the time—in particular, the blurring of the distinction between civilian and military objectives.¹⁰⁹ These challenges, in his view, required lawyers to redefine the law's basic rules. ‘Every war brutalizes those who participate in it as fighters; but no war leads to brutalization in the same way as modern irregular war.’¹¹⁰ Arguing that ‘normal international law’ was incapable of halting that brutalisation because it regulated only the overt part of irregular combat, Heydte wished for the ‘international law of tomorrow’ that would regulate also the covert dimension of irregular combat.¹¹¹ That new type of war required utmost attention as it encompassed various insidious tactics, such as propaganda that could affect the minds of Western youths, as it did in 1968.¹¹² Heydte urged his generation to meet its obligation: those who sought peace had a duty to prepare the law for the future war.¹¹³ The early 1970s saw Heydte writing a book exploring the challenges of contemporaneous irregular warfare for Europe, convinced that such a war ‘could break out tomorrow’.¹¹⁴ Therefore, he warned, ‘[N]ew international law norms must be found … before it is too late for our generation, and for our home, Europe.’¹¹⁵

C. The Adoption of the Definition: Edinburgh, 1969

As noted earlier,¹¹⁶ the Institut, still very much a West European Institution, provided Heydte with an amenable venue for his mission. When Heydte's Fifth Commission was established, the Institut lacked members from Afro-Asian nations, and the members of the Commission were mostly West Europeans.¹¹⁷ It took ten years for Heydte and his Commission to complete their mission. The first several years saw internal debate over whether or not it should even pursue its mission.¹¹⁸ Heydte was clearly in favour (noting that his fellow commanders in the Bundeswehr, who wished to comply with the laws of war, were waiting for the current ‘gross uncertainty’ to be clarified).¹¹⁹ A preliminary report in 1961¹²⁰ was followed by a provisional report in 1964,¹²¹ with a final report and draft resolution presented to the 1967 session.¹²² That draft resolution (subject to some modifications) was adopted in 1969 with overwhelming support.

The debate at the Institut reflected concerns about military freedom of action more than humanitarian matters. American members were endeavouring to make sure that the decision did not affect the legality of nuclear weapons. Others, notably Röling (the Netherlands) and Tunkin (USSR), expressed reservations about the idea that victims would be as constrained by the law as aggressors and suggested that the former be spared the obligation to target only combatants.¹²³

Heydte's final speech was animated. In support of his proposal, he invoked several recent developments:¹²⁴ the request made in late 1966 by the United Nations (UN) General Assembly to the Secretary-General to study the consequences of using nuclear weapons;¹²⁵ the Secretary-General's report submitted a year later¹²⁶ and approved by the Assembly;¹²⁷ the subsequent 1968 session of the General Assembly, which called for complete nuclear disarmament,¹²⁸ and articulated the obligation to protect human rights during armed conflict;¹²⁹ and the 1968 Tehran Declaration on Human Rights, which called for the eradication of ‘[m]assive denials of human rights, arising out of aggression or any armed conflict’.¹³⁰ Heydte also noted the fact that, in the meantime, the ICRC—itself buoyed by these developments at the UN—had restarted its codification efforts by launching its twenty-first International Conference, to be held a few weeks later. Heydte framed these developments as reflecting ‘the legal opinion of the whole world on the subject’.¹³¹ In his view, leaving aside the question of the legality of weapons of mass destruction, ‘the limitations on conventional weapons are now evident’.¹³² He concluded his address with a plea to the Institut to face the challenge once and for all: ‘take a stand on the question of the fate of humanity. To remain silent on this matter would be to betray the sacred mission of the law of nations’.¹³³

The proposed definition and the Resolution in its entirety were embraced enthusiastically. The vote was 60 in favour, one against (Jessup), and two abstentions (Gros and Feliciano).¹³⁴ The debate reflected the points of view of established powers. Only a handful of Associate Members represented the developing world at the Institut in 1969, and all but one (who spoke against the definition but abstained at the vote) remained silent.¹³⁵ At the behest of Ruegger (an Institut member who was a former President of the ICRC and remained an active ICRC Committee member), the results were immediately transmitted to the ICRC, just in time for the momentous Istanbul Conference.¹³⁶

D. The Definition and its Significance

Heydte's final report included an elegant distillation of the variety of military objectives into an abstract and comprehensive formula:

There can be considered as military objectives only those that, by their very nature or purpose or use, make an effective contribution to military action, or exhibit a generally recognized military significance, such that their total or partial destruction in the actual circumstances gives a substantial, specific and immediate military advantage to those who are in a position to destroy them.¹³⁷

Heydte was not coy about his impressive achievement, which, he said, had been ‘the most difficult to resolve’ and had eluded international lawyers since the end of World War I.¹³⁸ The major innovation that synthesised different objects into such a workable formula was its insistence on the ‘very nature or purpose or use’ of the target as a condition for identifying a target as military, rather than solely focusing on the military advantage anticipated from the attack.¹³⁹ This abstract formula was immediately perceived to be sufficiently comprehensive and clear, and hence capable of limiting the discretion of military planners as well as fighters on the ground.

What helped Heydte secure the support of the Institut for the definition? What was the true impact of his definition? To answer these questions, it is necessary to pay attention to the evolving global political landscape. As Heydte himself, acknowledged,¹⁴⁰ 1969 was an opportune moment for his mission, with its rare confluence of different initiatives to restrain combat that harmonised into the new definition and its adoption. On the one hand, the newly-freed ‘third world’ had seized the so-called ‘International Year of Human Rights’ (1968) as an impetus for seeking to delegitimise the military use of nuclear weapons and otherwise setting limits to the overwhelming power of colonial nations. On the other hand, similar to the previous codification moment almost a century earlier,¹⁴¹ this impulse of resistance to power was successfully eclipsed at that moment by the dominant powers, concerned about the rise of irregular warfare or ‘the democratisation of the means of destruction’.¹⁴² The 1960s was also a period rife with wars of national liberation threatening the West. Irregular combatants found themselves prosecuted as criminals and executed for planting bombs in malls and otherwise targeting civilians.¹⁴³ Yet, a third impulse was the opposition within the West to the US bombings in Vietnam, which began in 1965,¹⁴⁴ ultimately prompting the Americans to use the law to clarify the legality of their operations.¹⁴⁵

But Heydte's motivation was different. In his writings, he describes what haunted him: the grave concern about intensifying irregular warfare against the established order. We might recall that Heydte had widely expressed his profound worry about the threat of irregular warfare and had called for the development of ‘new international law’ to address it. Heydte's goal—of using international law to limit irregular warfare—is also evident in his responses to comments during the Edinburgh session. The proposed definition, he emphasised, distinguished between the resistance characterised by World War II (which targeted military assets and, hence, was lawful) and the contemporary irregular fighters, who did not distinguish between military and civilian targets.¹⁴⁶ The application of the rule, Hydte explained, would doubly burden guerrilla forces: they would have to be discerning in their attacks, lest they be regarded as terrorists and treated as war criminals, stripped of POW status. But they themselves, their supporters and sympathisers, would be deemed lawful targets, and their hideouts qualify under the definition as military objectives. He pointed out that the nature of guerrilla warfare necessitates a wide definition of combatants: ‘the active groups that constitute the core of the guerrilla forces … [include] sympathizers, who are also combatants in the classic sense of the term, since they carry out reconnaissance operations, transmit information, ensure communications and transmissions, supply the guerrilla forces with arms and food and hide the insurgents’.¹⁴⁷ But he declined to attempt to offer a clear definition of ‘combatants’ in the Resolution. Although one could not separate the two questions, Heydte explained, the Resolution's aim was to define ‘military objectives’, and not to specify who a combatant is. In his view, it sufficed that the Resolution asserted without further elaboration the general principle that there is an obligation to respect the distinction between ‘persons participating in the hostilities and members of the civilian population’.¹⁴⁸

As the deliberations made clear, the definition of military objectives and the general reference to civilians ‘participating’ in hostilities privileged countries that observed a neat separation between combatants and civilians. Other participants understood the implications. Quincy Wright remarked that applying the definition to irregular forces did not restrain their opponents, the regular armies. After all, ‘it was practically impossible to distinguish the civilian population from guerrilla forces’.¹⁴⁹

Heydte's definition would rebrand irregular warfare that targets civilians as ‘terrorism’.¹⁵⁰ Indeed, the Institut's definition would be the first text to offer a definition of what terrorism is, albeit indirectly. It would also be the only such text. Subsequent attempts to define ‘terrorism’ would fail to bridge the gap between subjective conceptions of terrorism.¹⁵¹

Key to Heydte's counterterrorism mission was his emphasis on the applicability of the 1969 Resolution also to non-international armed conflicts, as a matter of existing law. The preamble states that ‘the following rules form part of the principles to be observed in armed conflicts by any de jure or de facto government, or by any other authority responsible for the conduct of hostilities’.¹⁵² Heydte took pains to emphasise that the Resolution reflected customary international law. Opposing Quincy Wright's assertion that the Resolution went ‘much further’ than the Charter of the United Nations but was a ‘necessary innovation’,¹⁵³ Heydte insisted that the principle of distinction was one of the fundamental principles applicable to any armed conflict.¹⁵⁴ This position was accepted. Article 1 asserts that ‘[t]he obligation to [distinguish] remains a fundamental principle of the international law in force’,¹⁵⁵ and the text of the Resolution is replete with references to prohibitions found in ‘existing international law’.¹⁵⁶

The definition served the US's interests well in the early 1970s. If, in 1965, the US military had an arguable case¹⁵⁷ to claim that, in planning for attacks, there was no rule that would require the minimisation of civilian casualties,¹⁵⁸ the failures of US bombing campaigns in Indochina and the massacre in My Lai¹⁵⁹ led even US military lawyers to acknowledge that targeting civilians or causing them excessive collateral harm should be prohibited. When US Senator Edward Kennedy demanded a clarification from the Department of Defense about the legality of the US bombing in Indochina, he asked specifically whether the Department accepted the Edinburgh Resolution ‘as an accurate restatement of international law’.¹⁶⁰ The response reflected a nuanced retreat of the US military lawyers from their initial rejection of the principle of distinction as legally required,¹⁶¹ and portended the definition accepted in API. Referring to the Edinburgh Resolution, the response critiqued only the demand that ‘there must be an “immediate” military advantage’, as failing to ‘reflect the law of armed conflict that has been adopted in the practices of States.’¹⁶² Obviously, by now, the US Government and military endorsed Heydte's formula, appreciating its usefulness for their cause.¹⁶³

E. Heydte's Definition Codified, 1969–77

The Edinburgh Resolution's breakthrough moment was timely, from the perspective of the ICRC. Buoyed by the ‘United Nations human rights community’¹⁶⁴ and the UN Secretary-General's Report on ‘Respect for Human Rights in Armed Conflicts’,¹⁶⁵ which may have created ‘a certain spirit of rivalry and of competition for primacy’ between the UN and the ICRC,¹⁶⁶ the ICRC was now able to integrate Heydte's definition of military objectives into its renewed effort to transform the Hague law as part of the new vision of IHL.¹⁶⁷ As noted by Page Wilson, it was at the Istanbul Conference that the ICRC expanded its remit to include the ‘reaffirmation and development of the laws and customs applicable in armed conflict’,¹⁶⁸ beyond the Geneva law that applied hors de combat. Drawing on Heydte's strict definition, the ICRC was able to position humanitarianism as the overriding consideration for IHL.¹⁶⁹

Once adopted by the ICRC at the Conference, Heydte's formula became the basis for the ICRC's preparations for the Diplomatic Conference (1974–77),¹⁷⁰ convened to deliberate and develop the Additional Protocols. The ICRC's version followed the formula, while some of the modifiers were replaced (‘substantial, specific and immediate’ military advantage was replaced by ‘definite’ advantage), reflecting some countries’ concerns.¹⁷¹ This formula was ultimately adopted, without too much debate,¹⁷² as Article 52(2) of API. Leslie Green was one of the few who noted the ‘major significance’ of the Edinburgh Resolution.¹⁷³ Dieter Schindler regarded the 1969 definition as ‘the essential basis’ in substance and form of the corresponding definition in API.¹⁷⁴ However, the ICRC Commentary on the Additional Protocols fails to acknowledge the significant influence of the Institut on the definition adopted in API. Regarding API, it mentions the 1969 definition, albeit as part of a ‘study [of] weapons of mass destruction’,¹⁷⁵ while on the Additional Protocol II concerning non-international armed conflicts (APII) it simply states that ‘[t]he fundamental principles of protection which the [ICRC 1957] draft laid down were subsequently reaffirmed, first in a number of resolutions of the International Conference of the Red Cross, and later by those of the United Nations’.¹⁷⁶ It is interesting to note that Heydte, himself, did not mention the 1969 Resolution in his subsequent writings on the topic¹⁷⁷ or in his autobiography.

IV. THE AFTERLIFE OF THE 1969 RESOLUTION: A HAPPY ENDING TO A TORTUOUS TRAJECTORY

The adoption of Heydte's definition by the parties to the Diplomatic Conference on API raises a puzzle: how could a multi-party process that involved not only assertive Afro-Asian nations challenging the Western agenda but also several national liberation movements (NLMs),¹⁷⁸ which openly rejected the very feasibility of distinction during irregular warfare,¹⁷⁹ embrace Heydte's Eurocentric lawfare-grounded definition? The answer, as this Part will show, lies in the fact that, while the definition was adopted, it was effectively retooled by API to constrain regular armies while relieving irregular combatants of any consequence for ignoring it, both in international and non-international armed conflicts. But there is a happy ending to this twisting tale: with the rise of international criminal adjudication in the late 1990s and early 2000s, the definition was finally extended to protect all civilians who may be affected by battles of all types.

The context of API transformed Heydte's formula to a burden applicable exclusively to regular armies, whereas irregulars were effectively exempted from the responsibility to abide by it. This was achieved by tightening the rules on targeting in a number of ways. Civilian ‘sympathisers’ of irregulars would no longer be considered legitimate targets, since API strictly limited the scope of combatants only to those ‘taking direct part in hostilities’;¹⁸⁰ API further required that an attack should be called off if it was likely to ‘excessively’ harm civilians;¹⁸¹ and, during attacks, ‘constant care’ and ‘reasonable precautions’ would have to be taken to spare civilians.¹⁸² Complying with these requirements would prove a tall order for armed forces fighting irregular forces from that point onward.

Moreover, in what some considered a ‘serious blow to the humanitarian cause’,¹⁸³ the definition of military objectives was excised from APII, which instead provided a paltry provision admonishing parties against attacking civilian objectives, but without defining them.¹⁸⁴ States emerging from decolonisation had little appetite for international norms restricting their responses to internal challengers. Some of them even argued that ‘the objectives attacked in non-international conflicts may not necessarily be “military” ones’.¹⁸⁵

The final swing of the pendulum toward the decolonising world came with the recognition of NLM fighters as entitled to PoW status even if they disregarded the definition. This outcome was the result of the exclusion of the definition from the list of ‘grave breaches’ of API that would expose PoWs to war crimes charges.¹⁸⁶ During preparatory sessions with the ICRC,¹⁸⁷ and during the meetings of the Diplomatic Conference, NLM representatives explicitly eschewed the principle of distinction as incompatible with their strategy. George Silundika of the Zimbabwe African People's Union asserted that ‘the very nature of an anti-colonial war is that you are fighting an enemy that deprives you of any possibilities of fighting in the conventional manner’.¹⁸⁸ Mr Armaly, the representative of the Palestine Liberation Organization, asserted that ‘there were situations in which, owing to the nature of the hostilities, it was not possible to distinguish between combatants and the civilian population’.¹⁸⁹

Ultimately, then, Heydte's mission not only failed but even backfired. In subsequent years, he would continue to emphasise the pressing need to develop new international law to fight terrorism.¹⁹⁰ Perhaps the only solace for concerned Europeans such as Heydte was the implied proposition that urban guerrilla activities threatening the European metropole remained unlawful: the reference in the Additional Protocols to ‘armed’ conflicts meant that ‘“wars of national liberation” can only be legitimated under international law if fought mainly by military means, ie by acts of combatancy against military targets belonging to an enemy's armed forces’.¹⁹¹

The ICRC and other active promoters of the two Additional Protocols were not blind to the asymmetric outcome that posed inordinate risks for civilians.¹⁹² But they were hoping that the successful adoption of two sets of rules would allow them to incrementally reshape how the Additional Protocols were widely understood. The ICRC's Commentaries add gloss to the adopted texts by referring to the definition of military objectives among the rules applicable in NIACs,¹⁹³ as well as the definition of ‘grave breaches’ under API, thereby exposing irregular combatants to war crimes charges.¹⁹⁴

The proper balance, protecting all civilians equally, was ultimately reached with the turn to international criminal adjudication. The ‘stunning’¹⁹⁵ decision by the International Criminal Tribunal for the former Yugoslavia (ICTY) in 1995 to extend the customary laws of war to NIACs¹⁹⁶ meant that the consequences of ignoring the definition would be equally felt on all sides. Although States Parties to the Rome Statute of the International Criminal Court were unable to reach agreement on referring to the definition as an element of a crime in NIACs, it was referred to in several amended treaties.¹⁹⁷ The ultimate explicit endorsement of the definition as applicable to regular and irregular combatants fighting both types of war was rendered by the ICTY in 2005,¹⁹⁸ followed by the ICC in 2010.¹⁹⁹

V. CONCLUSION

The forgotten story of the birth of the definition of military objectives is relevant to the ongoing discussion that started with the events of 11 September 2001, about the need to update the laws of war to adapt them to irregular warfare, better known today as ‘asymmetric warfare’.²⁰⁰ It cannot be ignored, however, that the challenges of asymmetric warfare were already well-known to the law's codifiers, who saw the law as a suitable response to them. Whether or not its authors were correct, and whether the law now needs refinement, are questions that call for constant reassessment, but the argument that the existing law did not intend to restrict action during asymmetric warfare, and instead was designed to ‘deal with limited wars between roughly equal states’ is plainly erroneous.

The Institut's 1969 Resolution marked a watershed in the history of the codification of the laws of war. It provided one of the key provisions of the Additional Protocol I of 1977—a general, comprehensive and objective criterion for distinguishing between military and non-military objectives. This test would single out irregular fighters’ choice of targets as ‘terrorism’ that is subject to criminal sanctions, while allowing attacks by established powers on civilian neighbourhoods that would give them shelter. But that was only the first salvo in a battle of definitions that ultimately ended by judicial fiat.

The history of the codification of the principle of distinction is a microcosm of the larger history of the codification of the laws of war since the mid-nineteenth century. This is a story of how the laws of war were codified not only with the humanitarian mission in mind, but also, for some key actors, with the intention to use the law to address internal challenges to the incumbent governments of Western Europe. This is also an institutional story about the importance of venue and the implication of inclusion or exclusion of relevant voices. Heydte's achievement was possible only in the exclusive venue of the Institut, which still carried a heavy Western bias in 1969. The rise of the Non-Aligned Movement subsequently upended Heydte's achievement. Only judicial intervention a generation later would achieve a balanced outcome.

While the 1969 Resolution and its aftermath may be imagined as a battle between two adversaries to draft the shared rules, struggling for control of the pen, ultimately it was the judge who decided, as is often the case. The judges did so by imagining a history of linear progress of the evolution of norms constantly striving for more humane treatment in war. Such ‘discipline optimism’²⁰¹ empowered judges to assert that ‘[t]he protection of civilians in time of armed conflict, whether international or internal, is the bedrock of modern humanitarian law’²⁰² while expanding the scope of applicability of the 1969 definition as if it had always reflected customary international law.